An image display sheet including a lenticular lens and an image forming layer has been known as an indicator (marker) employing a combination of a lens and a mark. The lenticular lens has a configuration in which a plurality of cylindrical lenses are arranged side by side. The image forming layer serves as marks respectively corresponding to the cylindrical lenses. When the indicator is viewed from the convex surface portion side of the cylindrical lenses, a moved or deformed image of the marks is observed depending on viewpoints. The indicator is useful as a marker for recognizing the position, attitude, and/or the like of an object in the fields of Augmented Reality (AR), robotics, and/or the like. In addition, various studies have been conducted on the arrangement of marks for different uses, for example (see e.g., Patent Literature (hereinafter, referred to as “PTL”) 1 and PTL 2).